1. Field of Invention
The present invention is a barrier means to be attached to electrical cables, hawsers and the like lines for preventing rodents and other small animals from passage thereover and for thus preventing entry into buildings, ships, and boats. The invention constitutes a passageway that permits exit but not entry.
2. Related Prior Art
Rat guards or rodent barrier means have been used around ship hawsers for many years now. Such guards prevent rats, other rodents, and animals on the shore from boarding the ship by simply walking along the hawsers and entering the ship. Heretofore, such guards generally comprised large circular disks split into two hinged halves and clamped in some fashion on the ship hawsers. Despite these precautions, the rodents and animals have often been able to jump over the guards and board the ship without paying any fare.
Entry into buildings through electrical cables has also been a common occurrence for many decades. However, no known solution has been available for preventing these disadvantageous, if not damaging, trespasses.
The features of many of the rat guard inventions has consisted solely of a single circular disk attached to the line. An example of such a device would be a teaching by Salvarezza (U.S. Pat. No. 3,872,818) which discloses a rat guard for ship hawsers. The rat guard is a polygonal barrier plate having a generally flat bottom portion and a top portion with two steep converging edges meeting at a narrow vertex at the very top. The bottom portion is connected to these top converging edges by two upwardly diverging sides one of which has a slot that extends at an angle to the center of the guard. A door is provided to move into the slot and closing around the hawser once the guard is inserted upon the hawser.
Another example of a teaching of a rat guard is by Bush (U.S. Pat. No. 2,459,060) disclosing a guard having a circular plate with a slot and a closing door.
Another example of a teaching of a rat guard is by Bernhard (U.S. Pat. No. 2,483,874) which discloses a circular plate made of two halves with a closable slot.
Yet another teaching of a rat guard is one my Mucke (U.S. Pat. No. 2,525,234) disclosing a substantially frusto-conical shield with a slot to insert the hawser therethrough.
Yet another example of a rat guard is taught by Carver (U.S. Pat. No. 2,488,466) disclosing a circular plate with a hole near the center. On the back side of the circular plate discloses a cage to catch the rat leaving the ship. The cage allows for entry of the rat but prevents exit.
Yet another example of a rat guard is taught by Roberts (U.S. Pat. No. 4,782,622) which discloses a rat guard having a tubular body cut in half to be mounted on a hawser and which allows for entry of the rodent into said tubular body. The tubular body further has provision for storing toxic chemical compounds active to repel or destroy rodent or insect vermin.